This week, the overall grades of nine Semiconductor stocks are lower, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Avago Technologie (NASDAQ:AVGO) is on the decline this week, earning a D (“sell”) after receiving a C (“hold”) last week. Avago Technologies designs, develops, and supplies a range of analog semiconductor devices, focusing on III-V based products. The stock price has dropped 6.2% over the past month, worse than the 3.8% increase the Nasdaq has seen over the same period of time. For more information, get Portfolio Grader’s complete analysis of AVGO stock.

This week, ReneSola’s (NYSE:SOL) rating worsens to a D from the company’s C rating a week ago. ReneSola develops, manufactures and sells solar wafers, which are thin sheets of crystalline silicon material mainly made by slicing monocrystalline or multicrystalline ingots. The stock receives F’s in Earnings Growth, Earnings Revisions, and Equity. Cash Flow and Margin Growth also get F’s. To get an in-depth look at SOL, get Portfolio Grader’s complete analysis of SOL stock.

Ultra Clean Holdings’ (NASDAQ:UCTT) rating falls this week to an F (“strong sell”), down from last week’s D (“sell”). Ultra Clean Holdings is a developer and supplier of critical subsystems, mainly for the semiconductor capital equipment industry. The stock gets F’s in Earnings Growth, Earnings Momentum, and Earnings Revisions. For a full analysis of UCTT stock, visit Portfolio Grader.

SunPower (NASDAQ:SPWR) experiences a ratings drop this week, going from last week’s C to a D. SunPower is a vertically integrated solar products and services company that designs, manufactures, and delivers solar electric systems worldwide for residential, commercial, and utility-scale power plant customers. The stock gets F’s in Equity, Cash Flow, and Sales Growth. To get an in-depth look at SPWR, get Portfolio Grader’s complete analysis of SPWR stock.

The rating of Silicon Laboratorie (NASDAQ:SLAB) declines this week from C to a D. Silicon Laboratories designs and develops proprietary, analog-intensive and mixed-signal integrated circuits that can be used in a range of applications. The trailing PE Ratio for the stock is 31.80. For a full analysis of SLAB stock, visit Portfolio Grader.

Slipping from C to a D rating, Cavium (NASDAQ:CAVM) takes a hit this week. Cavium designs, develops and markets semiconductor processors for intelligent and secure networks. The stock receives F’s in Earnings Growth, Equity, Margin Growth, and Sales Growth. Share prices fell 9.1% over the past month. As of Jan. 9, 2013, 13.6% of outstanding Cavium shares were held short. For more information, get Portfolio Grader’s complete analysis of CAVM stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.